Seaways Free Article: An alarming situation
When bridge technology is distracting
by Dmytro Rodyhin
During pilotage, every member of the bridge team must actively contribute to the vessel’s safe conduct. The Master oversees the overall operation; the pilot provides local expertise and cons the vessel; the Officer of the Watch (OOW) supports navigation via position monitoring, traffic assessment, communications, and under-keel clearance (UKC) control; while the helmsman and lookout maintain steering and observation. In this high-stakes phase of navigation, human attention is one of the bridge team’s most valuable resources.
Yet, during some port approaches, a critical team member, usually the OOW, can devolve into an alarmsilencing operator.
This happens in an entirely ordinary way. Imagine a vessel approaching port under pilotage. At some point, the vessel intentionally deviates from the planned route to accommodate local port conditions. This move is expected, understood, and actively monitored, and the vessel remains in safe waters. The ECDIS, however, blindly compares the vessel’s position to the pre-planned route and begins generating relentless audible cross-track alarms.
As the vessel enters shallower port waters, the echo sounder joins in. This depth change is also entirely expected. The bridge team is already monitoring the underkeel clearance (UKC), the pilotage plan and the depth trend, but the alarm is tied to a fixed shallow-water value. The alarms are acknowledged. Seconds later, they sound again. They are acknowledged again. The sound again. And repeat.
On one port approach I experienced, these alarms sounded so frequently that the OOW was pressing the ‘Stop Alarm’ button almost continuously. Instead of contributing to traffic observation or position monitoring, their attention was hijacked by the alarm-handling process. While no accident occurred and the team remained in control, the situation raised a critical question: can some bridge alarms, though technically correct, become operationally unhelpful – even hazardous – during pilotage?
Technically correct, operationally unhelpful
The problem is not that these alarms exist; it is that they fail to account for the operational phase of navigation. During open-sea or coastal transits, a route deviation may signal a genuine navigational crisis; the vessel may be standing into danger or drifting off course. In those contexts, an audible alarm is invaluable.
During pilotage, however, the context changes entirely. A vessel frequently leaves the planned track for legitimate tactical reasons, such as pilot advice, tug operations, or VTS instructions. Under these circumstances, a repeating audible alarm adds no safety value. The bridge team already know they are off-track; the deviation is intentional. An alarm blaring every few seconds is just one more distraction during one of the most demanding phases of navigation.
Variable alarm limits linked to the passage plan can certainly help and should reduce unnecessary alarms when they are properly set. However, while well-prepared route-based limits may reduce nuisance alarms, they cannot remove the problem completely, particularly if there is a shift into tactical navigation.
The echo sounder suffers from the same lack of contextual awareness. While a shallow-water alarm in open water is a stark warning of danger, decreasing depth during a port approach is a feature of the voyage, not a bug. Again, a reduced alarm depth for the port area can help, but it may still not fully reflect the expected depth profile, UKC trend and local pilotage situation, as the vessel is expected to move into dredged channels, turning basins, or berth pockets.
If the alarm logic relies solely on a single, fixed-depth value, it will trigger repeatedly, even if the vessel maintains a perfectly safe UKC that aligns with the passage plan and tidal data. If the condition is expected and safe, the audible alarm adds noise, not safety.
Rather than asking ‘Is the depth below a fixed value?’ a smarter system would align with the passage plan to ask: ‘Is this depth dangerous for this specific vessel, in this location, during this phase of navigation?’
Alarm fatigue
Alarm fatigue is driven by alarms that fail to offer actionable information. When alarms sound constantly for expected conditions, crew become conditioned to treat them by silencing rather than investigating. This is not a matter of poor crew attitude; it is a predictable human response to a system that demands attention without providing new insight.
Bridge teams are forced to choose between two flawed options:
- Keep all alarms active and accept constant, high-stress distraction.
- Silence or desensitise alarms and risk missing a genuinely critical warning.
A third option should be possible: keep critical danger alarms active, but reduce repeated audible alerts for expected operational conditions.
A solution: Pilotage mode
The solution could be a dedicated ‘pilotage-aware alert management’ mode for ECDIS and echo sounders. The underlying philosophy is simple: Silence expected conditions after the first alert; never silence danger.
This mode would not disable safety features. Instead, it would adjust how repeated alerts are handled during tactical navigation. For example, if a vessel intentionally leaves the track under pilotage, the ECDIS would sound a single initial audible alert, then transition to a clear, persistent visual status: Outside Planned Route – Pilotage Mode Active.
The audible alarm would then remain quiet unless the vessel approached a genuine, secondary safety boundary. The event is still logged, and route monitoring remains active, but the audio pollution is eliminated. The same logic applies to the echo sounder: if the depth matches the expected profile and maintains safe UKC, the system remains audibly silent, saving its voice for sudden anomalies or critical breaches.
To ensure this mode is never used to suppress vital data, certain critical alerts must remain non-suppressible:
- Approach to safety contour/ grounding risk;
- Crossing a no-go area; Loss of vital sensor inputs;
- ECDIS system failures;
- UKC falling below the agreed absolute minimum safety limit;
- Sudden, abnormal depth deviations from the expected profile.
mplementing this does not require a total navigational overhaul; it uses data already available on most modern bridges (vessel position, speed, route, draft, and minimum UKC).
The process would be as follows:
- Define the zone: The passage plan includes a designated ‘Pilotage or Tactical Navigation Zone’.
- Activate the profile: Before entering the zone, the Master or OOW manually confirms and activates the Pilotage Alert Profile, an action that is automatically logged.
- Smart monitoring: Repeated audible tracking alerts are suppressed after the first acknowledgement, while visual indicators remain clear.
- Automatic reversion: Upon leaving the pilotage area, the system prompts the team to return to normal seagoing route monitoring.
To prevent misuse, this profile would require formal confirmation to activate, be restricted to authorised geographical areas, and always preserve core safety boundaries.
Reclaiming space
Paradoxically, many safety initiatives in shipping increase crew workload by adding checklists, permits, or reporting requirements. There is a constant danger that safety measures become heavier rather than smarter.
The issue of nuisance alarms is a prime example. The question should not be ‘How can the OOW manage alarms better?’. The real question is whether our systems can be designed to support the bridge team more intelligently. Good safety design should remove unnecessary friction.
When an officer is forced to repeatedly press a button during a critical transit, the system is wasting human cognitive capacity. That attention must be reclaimed for what matters: maintaining clear situational awareness for navigation, traffic monitoring, and communication.
The goal is not a quiet bridge for comfort, but a bridge where every audible alarm merits immediate, unquestioned attention. By introducing operational phase awareness into alarm design, we can increase safety without increasing the burden on the crew.